Mismatch DNA repair mRNA expression profiles in oral melanin pigmentation lesion and hamartomatous polyp of a child with peutz–jeghers syndrome

Mismatch DNA repair (MMR) mRNA expression analysis was performed on a biopsy of oral mucosa melanin pigmentation lesion, a hamartomatous polyp and peripheral blood derived from a 12‐year‐old child with Peutz–Jeghers Syndrome (PJS). We present a deficient MMR system, in a PJS patient, which demonstrated low mRNA levels of hMSH6 and hPMS2 and an increasing MMR deficiency from the non‐dysplastic lesion to hamartomatous polyp of PJS with a high risk of cancer. Pediatr Blood Cancer 2013;60:E116–E117. © 2013 Wiley Periodicals, Inc.